Local area networks ("LANs") are widely used for electronic communication between computerized user devices. One problem which has been recognized with LANs is a tendency for background communication traffic, which user devices must process, to slow the user devices and thereby adversely affect productivity. Accordingly, it is desirable to reduce the background traffic processing overhead.
One way in which background traffic processing overhead is reduced is through the use of virtual LANs ("VLANs"). In the VLAN model a LAN is divided into multiple VLANs, each of which is made up of user devices which share some common trait. For example, a VLAN might include the user devices of a group of workers in a given department if it is assumed that such workers are likely to communicate most frequently amongst themselves. Intra-VLAN Traffic is then segregated to facilitate communication within each VLAN. For example, IEEE Standard 802.1q dictates that a "VLAN tag" be used to identify the VLAN from which a packet of data is transmitted. The VLAN tag is then used to filter packets. Consequently, user devices which are not associated with the VLAN indicated by the VLAN tag need not be slowed by intensive processing to determine whether such packets are destined for such user devices.
While VLAN identification tagging reduces overall traffic overhead, inter-VLAN communication remains problematic. Typically, all inter-VLAN communication is mediated by routers which maintain connectivity tables that indicate the location of various VLANs within the LAN. In a large enterprise LAN there may be multiple router hops between VLANs. This is undesirable because routers are relatively slow in comparison with other network devices, and hence multiple router hops can introduce significant undesirable delay. Further, inter-VLAN communication may create background traffic overhead. A technique for facilitating inter-VLAN communication which reduces such traffic would therefore be desirable.